The comments give reason to believe this isn't the cause, but my first instinct was that NaN cannot be equal to NaN as it isn't clear what the object represents

The comments give reason to believe this isn't the cause, but my first instinct was that NaN cannot be equal to NaN as it isn't clear what the object represents. As Mike C states in his answer: "Another way to look at it is that NaN just gives you information about what something ISN'T, not what it is." But is this an effective way of looking at the question? In reality what you're trying to do is not compare a NaN to another NaN, you're actually attempting to check if both objects are NaN. This hurts my brain.